Stu Bell wrote: > Jim Brain wrote: > [...] >> Can someone clarify why these macros are preferred over doing >> cli()/sei()/SREG=sreg in code? I'm not trying to troll, but >> wonder if there is something I am missing. > [...] > More important, in my mind, is that the macros are written in such a way > that the enclosed code is guaranteed not to be optimized out of the > block.
This for me is the most important and most surprising point to newbies: code can be moved out of a cli() / sei() block by compiler optimizations because sei() is not a compiler barrier at all (just search for a previous thread '"cli" and "sei" should clobber memory'). > [...nice sum up of atomic_* advantages trimmed...] -- Paulo Marques Software Development Department - Grupo PIE, S.A. Phone: +351 252 290600, Fax: +351 252 290601 Web: www.grupopie.com "All I ask is a chance to prove that money can't make me happy." _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
